This invention relates in general to a cleaning assembly for an electrostatographic reproduction apparatus, and more particularly to an improved cleaning assembly which includes a cleaning blade, attached to the housing of a vacuum-assisted cleaning brush, in engagement with the dielectric member web to be cleaned so as to deflect such dielectric member web.
In a typical electrostatographic reproduction apparatus, a latent image charge pattern of information to be copied is formed on a dielectric member and thereafter developed with charged pigmented marking particles. The charged marking particles adhere to the latent image charge pattern on the dielectric member to form a developed image. The developed image is then transferred to a receiver member to form the desired reproduction of the information to be copied. After transfer of the developed image, any residual marking particles remaining on the dielectric member are removed and the dielectric member is reused by having subsequent latent image charge patterns formed thereon.
Efficient cleaning of the dielectric member is required to prevent undesirable artifacts from being produced on the copied information. One method for removal of the residual marking particles from the dielectric member after transfer is typically accomplished by scrubbing the surface of the dielectric member with a rotating brush operating in a vacuum atmosphere to attract the particles (and any additional debris) from the dielectric member and transport the particles to a remote collection chamber. Another method for removing residual marking particles includes scraping the dielectric member with a cleaning blade.
In modern high-speed electrostatographic reproduction apparatus, the dielectric member is, for example, a flexible web movable about a closed loop path in operative association with the electrographic process stations. In certain instances, the dielectric member cleaning brush or cleaning blade does not prove efficient in removing the residual marking particles or debris from the web. As noted, this results in undesirable artifacts being formed on the copies of the information being reproduced. As such, yet another method for removing residual marking particles has been proposed. This method utilizes a rotating brush combined with a scraping blade (see for example U.S. Pat. Nos. 3,918,808; 4,640,599; and 4,984,028).
Further, in the recent U.S. pat. Nos. 4,989,047 (issued Jan. 29, 1991, in the name of Jugle et al) and 5,031,000 (issued July 9, 1991, in the name of Pozniakas et al), it is disclosed that the utilization of a blade cleaner in associated with the vacuum-assisted brush cleaner, to improve the overall effectiveness in the cleaning of a dielectric member web, is best accomplished when the blade is located at a very low attack angle relative to the dielectric member and engages the dielectric member with a very low pressure. The mechanism for providing such low attack angle/low pressure arrangement of this cleaning assembly is difficult to maintain in the desired relative position with the dielectric member web. Further, it is directed to a particular cleaning problem (i.e., agglomeration removal), and does not address other cleaning issues. As a result, it is not completely effective in carrying out the overall desired web cleaning process.